Subtitled 'Travels with Enduring People in Vanishing Lands', this deeply philosophical book considers that progress has not been good for everyone and a way of life which includes greener living, may be the solution for the human race. Jules Pretty talks about THE EDGE OF EXTINCTION in terms of human cultures and local economies. How do we retain and celebrate what has made cultures unique, while bringing the advantages of medicine and applied science?

Our journey begins by crossing the International Date Line to visit New Zealand, the last large land mass to be populated apart from Antarctica and reached by navigating Polynesians in outrigger canoes. Amid the descriptions of Maori culture and hospitality, I was fascinated to learn that the diaries of bird-harvesters were found to tally with El Nino years. Where coastal wetlands have been drained birds can no longer find eels to sustain their chicks. So humans also influence the ecology of their surrounding areas.

China is the author's next port of call, sporting intensive cultivation and global brands. Village houses have solar water heaters. Jules Pretty tells us that he came here thirty years ago, musing on some of the sweeping changes. Everything in the economy of the mountains is hauled up there by people. The Chinese come to walk on sacred mountains, amid ancient pagodas and temples, listening to portable music and taking photos. With the one-child policy, a cousin takes the place of a sister or brother.

In Australia, we learn that the land's original inhabitants were not permitted to vote or hold money until 1967. An astonishing trove of ancient petroglyphs, including extinct animals, sits uneasily by a spreading factory; the authorities do not give the rock art any protection. Strip mining of iron, salt and fertiliser production and liquid gas transportation take priority. We progress to Russia's steppes, where Tuvan migrant herdsmen are once more leading a traditional life after the collective farms closed. Next to Finland, feeling climate change, then Botswana and California.

Reading these detailed visits, I felt impressed but also cautious. I have read about the life of early twentieth- century farm workers in Ireland, and there is no way I would want anyone to have to return to that time. Living as a nomadic herdsman or fisherman, necessarily on the fringe of civilisation, would be cold, painful, hungry, physically strenuous, risky and isolating. There would be early deaths, especially for pregnant women, and high infant mortality.

I've seen that in modern Turkey the government gives grants to shepherds for solar panels which are carried on donkeys, in order for them to power up laptops. This kind of helpful compromise allows people to live the way they choose, with modern assistance and contact. Cellphones, charged by solar panels worn on a backpack, may carry an app to diagnose eye diseases such as cataract and glaucoma on the spot, so doctors can provide targeted treatment to remote areas. An origami microscope made of paper with inbuilt lenses and LED light source, can be used to diagnose diseases such as malaria. No such solutions are offered by Jules Pretty however; the author merely records his observations. For this reason I suggest that THE EDGE OF EXTINCTION should be read along with a hard look at what useful, light technology can do to reduce isolation and provide healthcare.